FIGS. 14 and 15 show an example of conventional shearing apparatus similar to the apparatus noted above. In the illustrated example, a main roll body 91 has a rotating roll 93 mounted on a surface thereof and defining ridges 92 as integral parts of the roll 93 for producing a predetermined design pattern. This rotating roll 93 is placed under a spiral cutter 94. As a pile fabric 97 having a multiplicity of piles 96 formed on a foundation 95 is transported by a transport device (not shown) in the direction of an arrow in FIG. 14, tip ends of the piles 96 are sheared between the spiral cutter 94 and a lower blade 98.
According to this conventional apparatus, the piles 96 corresponding to the ridges 92 are cut short, while the piles 96 corresponding to the main roll body 91 are cut long. Although this apparatus has the advantage of providing the predetermined design pattern, the pattern is only repeated in a fixed manner according to the configuration of the ridges 92 on the rotating roll 93. Not only is a different rotating roll having ridges 92 in a different configuration required to produce a different design pattern, but a simple repetition of the pattern is obtained.
To overcome the above disadvantage, Applicants have invented a shearing apparatus as disclosed in the Japanese patent application laid open under No. 60(i.e. 1985)-75662.
This prior shearing apparatus includes a plurality of elements vertically movably arranged on an element block. These elements are individually projected by piston rods of air cylinders. Air supply to the air cylinders is effected and stopped under control of a control unit based on signals received from a pattern reader, thereby producing varied design patterns.
In this prior apparatus, however, the above elements inevitably are arranged with gaps in between by reason of the outside diameter of cylinder tubes of the air cylinders provided for controlling these elements individually. It is therefore difficult t obtain fine design patterns although coarse design patterns may be obtained.